Drill



Jan. 22, 1946. s. E. MEINERT DRILL Filgd Nov. 8 1943 I N V EN TOR. 53/1 yes ff! 5'. file/12in- BY W a HZ'TORNEY Patented Jan. 22, 1946 UNITED STATES PATENT OFFICE DRILL Sylvester E. Meinert, Wynnewood, Pa.

Application November 8, 1943, Serial No. 509,411

1 Claim.

This invention relates to drills wherein the drill bit and bar are constructed separately and adapted to be detachably connected to form a unitary drill structure.

It is an object of the invention to provide a drill bit and bar in drills of this character with means projecting from theend of the bit opposite the cutting face and an end of the bar adapted to be interengaged to attach the bit to the bar, andarranged to prevent lateral displacement of the bit relative to the bar, and to provide resilient means adapted to be readily engaged with the interengaged portions of the bit and bar to releasably secure the bit and bar together and prevent axial displacement of the bit from the bar in the use of the drill, and to be readily and quickly removed to permit detaching the bit from the bar should it be desired to remove the bit to sharpen the same, or to substitute another bit, or for any other purpose.

It is another object of the invention to provide an improved drill of this character wherein the "end of the drill bit and an end of the drill bar are arranged with means adapted to be interengaged and disengaged by aXial movement of the drill bit and bar one relative to the other to attach and detach the "bit from the bar, and said means arranged to prevent displacement of the bit laterally of the bar and to transmit rotary movement of the :bar to the bit, and means adapted to be disposed about and engaged with the interengaged portions of the bit and bar to releasably secure the bit to the bar and permit the bit to participate in the axial movement of t'hebar.

It is a further object of the invention to provide a drill of this character wherein the end of the 'bit opposite the cutting face and an end of the drill bar are arranged with diametrically oppositely disposed projecting portions of segmental form in cross section and the spaces between the projecting portions arranged-of corresponding segmental form and adapted to be engaged by the projecting portions to detachably connect the bit to the bar, and the ends of said projecting portions and the recesses of the bit constituting seating faces substantially equal to the cross sectional area of the bit and bar adapted to take up in substantially the entire cross sectional area of the "bit the forces of impact transmitted to the bar, and the projecting portions of the bit 'andbar provided with peripheral recesses adapted to be engaged by a resilient ring member to releasably secure the bit to the bar.

In the drawing accompanyin and forming a.

part of this application, Figure 1 is a side elevation-of a drill bar and a drill bit releasably attached thereto embodying the invention.

Figure 2 is a 'cross sectional view taken on the line 22 of Figure 1 to show the arrangement of the interengaged projecting portions of the bit and bar and the resilient means engaging peripheral recesses in the projecting portions of the bit and bar to releasably secure the bit to the bar.

Figure 3 is a perspective view of a resilient ring disposed about and engaging in peripheral recess in the interengaged projectin portions of the drill bit and bar shown in Figures 1 and 2 to releasably secure the bit and bar.

Figure 4 is a side elevation of a bit embodying the invention.

Figure 5 is a view looking at the top of Figure 4.

Figure 6 is a side elevation of a portion of a drill bar showing an end arranged with the bit attaching projections, the bar being of less cross sectional dimension than the bit attaching end thereof.

Figure '7 is a View looking at the bottom of Figure 6.

Figure 8 is a perspective view of a modified form of securing ring, and

Figure 9 .is a cross sectional view of the interengaged projecting portions of a drill bit and bar showing a modified form of the peripheral recesses therein engaged by the bit securing ring member shown in Figure 8.

In carrying :out the embodiment of the invention shown in the drawing, there is provided a bar 10, constituting a drill bar, of any cross sectional form-and having an end portion preferably arranged of circular form in cross section, as shown at H, the bar having a bore 12 extended longitudinally 'therethrough. The circular end portion of the bar is provided with projections l3, in the nature of jaws, equidistantly spaced about the bar, and shown as two in number diametrically oppositely disposed, although a greater number of said projections equidistantly spaced about the bars may be used. The projecting portions I3 extend radially outward from the bore in the bar and are of segmental form in cross section, each projection extending through an arc of slightly less than degrees and arranging the end of the bar with recesses [4 between the projections of corresponding segmental form.

Abit 15 of conventional form has a bore [6 extending centrally therethrough, the bit having an end portion of circular form in cros section and of a diameter substantially the same as the circular end portion of the drill bar and is arranged at the opposite end with a cutting face consisting of a series of cutter edges ll, shown as 4 in number, equidistantly spaced about and extending radially of said end of the body and are of a length to extend outwardly from the body of the 'bit, as showninFigures '1 and 2. The portions of the body of the bit above the cutter of segmental form in cross section and extending, through an arc of slightly less than 90 degrees.

and. arranging recesses or spaces 2| between said projections of corresponding segmental form. The recesses 2! in the bit are adapted to have a projecting portions of the bit and bar. The bore in the bit and bar are in alinement and are adapted. for the conducting of a liquid, such as water, through the alined bores to flush chips and other residual materialfrom the cutting face of the bit and cause the same to flow rearwardly relative to the flutes I 8 and be discharged with the water from the drill hole. If desired the outmade of different cross sectional area than the sliding fit with the bar projection l3; and the bar recesses it are adapted to have a sliding fit with the bit projections 20, the bit being attached to the bar by axial movement of the bitand bar relative to each other and the interengagement V of the bitprojections Zil'with the bar recesses l4 and the bar projections 13 with the .bit recesses 2!. The drill bit and bar projections 20, I3 are provided intermediate the juncture of said projections with the body of the bit and bar and the ends thereof with peripheral recesses 22, '23

adapted to be disposed in alinement when the bitisassembled on thebarp To releasably secure the bit to the bar a resilient eXpa-nsible member, in the form of a split ring 24, as shown in Figure 3, is disposed about ring 24 is provided with portions extending in arcs of'a circle having different radii. As shown, the end portions 25 and the diametrically opposite portion 26 of the ring member 24 are in arcs of a circle having a longer radius than the intermediate arcuate portions 21 of the ring member, the end portions 25 and diametrically opposite portion 25 being adapted .tobe engaged in the recesses 23 in the bar projection ,i 3 and the intermediate portions 2! are adapted to engage in the recesses 22 in the bit projections 29 in the locking position of the ring. To release and remove the bit from the bar rotative movement is imparted to the locking ring by grasping the same between the thumb and index finger portion of the hand to cause the portions 21, of the locking ring to ride out of the recesses 22 in the bit projections 20 .into the recesses 23 in the bit projections I3 spreading the ends of the locking ring and thus facilitating removing the ring from the bit and bar recesses. To facilitate gripping and imparting rotative movement to the locking ring the outer surface thereof may be knurled. A Y,

By making the projecting portions of the bit and bar and the recesses between said projecting portions of segmental form, the projectingportions or jaws, when engaged in said recesses, cause the bit to be held against lateral displacement from the bar and any rotative movement of the bar may be transmitted to the bit. Also by this arrangement the ends of the projecting portions of the bit and bar and the bottom of the recesses, constituting seating faces, are substantially equal to the cross sectional area of the bit and bar and the bit is adapted to take up in substantially the entire orosssectional area thereof the forces of impacts transmitted to the bar without any possibility ofpeening or distorting the end of the bar arranged with the projecting portions [3, as shown in Figure 6, wherein the body of the bar is of circular form and less diameter than the end arranged with the projecting portions or-jaws. However, preferably the bit attaching end of the drill bar is ofa diameter equal to the diameter of thebody' of the drill bit.

The locking ring 24 may be of difi'erent forms. As shown at 24' in Figure B the locking ring is of uniform thickness and substantiall of uniform diameter. In the use of such ring. for securing the bit to the bar the recesses 22', .23, in the projecting portions or jaws 20', 13', of the bit and bar are substantially ofequal depth, whereby the outer surface of the ring in bit securing position is substantially flush withtheouter surface of the bit and bar, as shown in Figure 9. To apply the securing or locking ring shown in liigure -8, and in which manner the seguring'orlocking ring shown in Figure 3,1na Kal so be applied, it isex; paneled sufficiently to engage the same upon the projecting portions or jaws of the bit or bar to engage therewith at a side of the recesses and after the bit is assembled on. the bar the ring is slid along the bit or bar to cause it to engage in the alined recesses in the interengaged projecting portions or j aws of the bitand bar. To release the modified ring from securing engagement with the recesses a tool is provided to expand the ring sufiiciently to. permit engagement of the same about an unrecessed portion of the bit and bar. Having described my'invention, I claim:

g In a drill, a bar member and a bit member, the bit member having a cutting face at one end, one end of the bar member and the end of the bit member opposite the cutting face arrangedwith diametrically oppositely disposed projecting portions of like segmental form in cross section and the spaces between said projecting portions corresponding to the segmental form ,of the projecting'port'ions, and the bit member adapted to be assembled on the bar member by axial movements of the bit and bar members relative to each other with the projecting, portionsof one member engaging the spaces of the other member, and said projecting portions when thelbit member is assembled on thebar member holding the-bit and bar members against lateral displacement, and said projecting portions of the bar and bit members having peripheral recesses therein adapted to be disposed in alinement when the bit member is assembled on the bar member, the recesses in the projecting portions of one drill member bein of greater depth than the recesses in the projecting portions of the other drill member, and a split resilient ring arranged withdiametrically opposite portions having a longerradius than the portions of the ring alternate therewith and saidiportions having a longer radius adapted to engage in the recesses of less depth and the portions of the ring having a shorter radius adapted to engage in the recesses of greater depth. a

- SYLVES'IER E. MEINERT. 

